The present invention is generally directed to three-dimensional imaged nonwoven fabrics and the methods for employing such three-dimensional imaged nonwoven fabrics as a means for cleaning surfaces. A particularly preferred embodiment of a three-dimensional imaged nonwoven fabric of the present invention is in facial cleansing applications.
Over the years, the use of disposable substrates in cleaning applications has been well practiced. Suitable substrates have included sponges, woven and nonwoven fabrics, and various combinations thereof. Further, such substrates have been impregnated with cleaning agents such as astringents, solvents, detergents and other chaotropes. The resulting cleaning products fabricated from such impregnated substrates have found acceptance with the general public as a convenient and practical means for the cleaning of surfaces. In particular, such constructs have been reasonably successful in the facial cleansing market.
Substrates of particular importance in the facial cleansing market include those fabrics that are imparted with apertures, or otherwise exhibit regions devoid of substrate matrix. It is has been conjectured by the fabricators of facial cleansing products practicing the use of such apertured fabric that the presence of the apertures improve the ability of the substrate to quickly build a beneficial lather during the cleansing process.
The presence of apertures in a facial cleansing product has been found to be a difficult and complex material to fabricate due to a need to have an absolute minimum in the occurrences of occluded apertures. Occlusion of the aperture, for example by the fibrous matrix of a nonwoven substrate, has multiple deleterious affects. First, the occlusion results in an expected reduction of efficacy during a lather generation procedure due to the further constriction of the occlusion by the buildup of applied detergent agents. Second, an apertured substrate is difficult to fabricate so as to be functional and at the same time aesthetically pleasing. The very real problem of aesthetic appeal to the end-user is based on the fact that the human eye is attracted to variation in repeating patterns. An intermittent occlusion, even if only subtle in degree, will result in the user perception of a low quality product. The need for uniformity of aperture must be anticipated during the fabrication process and substrate material rejected should the aperture clarity at any time fall outside of predetermined specifications, thus leading to an exceedingly high level of potential material being rejected.
There remains a need for a disposable substrate for cleaning applications, and particularly facial cleansing products, which is capable of forming lather, and does not suffer from the deleterious affects inherent to apertured substrates.
The present invention is directed to enhancing the cleaning of surfaces by the contact application of a non-apertured nonwoven fabric having a three-dimensional image imparted therein. The three-dimensional image of the non-apertured nonwoven fabric induces the formation of lather due to pronounced surface projections that come in contact with the cleaning surface and provide air passageways that are parallel to the plane of the substrate. The imaged nonwoven fabric disclosed herein exhibits low Tinting qualities thereby reducing the potential of fiber contamination of the cleaned surface and is sufficiently durable that the sample can be used in a brisk manner.
A method of making the present durable nonwoven fabric comprises the steps of providing a precursor web that is subjected to hydroentangling. The precursor web is formed into an imaged nonwoven fabric by hydroentanglement on a three-dimensional image transfer device. The image transfer device defines three-dimensional elements against which the precursor web is forced during hydroentangling, whereby the fibrous constituents of the web are imaged by movement into regions between the three-dimensional elements of the transfer device.
In the preferred form, the precursor web is hydroentangled on a foraminous surface prior to hydroentangling on the image transfer device. This pre-entangling of the precursor web acts to integrate the fibrous components of the web, but does not impart imaging as can be achieved through the use of the three-dimensional image transfer device in subsequent steps.
It is further contemplated by the present invention that the use of a semi-durable three-dimensional imaged nonwoven fabric can be employed in facial cleansing applications, whereby three-dimensional image of the nonwoven fabric induces the formation of lather due to pronounced surface projections which come in contact with the facial skin and provide air passage ways necessary for lather propagation that are parallel to the plane of the non-apertured substrate. The imaged nonwoven fabric is further designed to facilitate optimal performance when used in the wetted state and when treated with or subject to surfactant compounds.
Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.